Current client is a Windows/.NET shop. There are some parts which use Linux, but that is more infrastructure, all the apps run Windows -- and rather well too!

Since when do applications 'run' operating systems?

Since at least 1999 or so when VMware showed up :)

:) VMWare is an application that runs operating systems, yes.

But a) original poster is talking about a web application; not a virtual machine or hypervisor and b) VMWare itself still requires an underlying operating system-- one could argue that this case is actually an operating system running another operating system with a thin adapter layer in between (i.e., the VMWare application).

> VMWare itself still requires an underlying operating system

VMware is a company, not a product - the product you're [probably?] referring to is ESX[1], which does not require an underlying OS - it's a Type 1 hypervisor (it runs on bare metal).

[1] https://en.wikipedia.org/wiki/VMware_ESX

I was actually referring to 'VMWare Workstation'. This company apparently has a habit of putting the company name inside all of its product names. That doesn't preclude one from referring to each its product offerings by short name.

The point that observer1101 is almost certainly trying to make is that "Apps run operating systems" in the sense that deploying an app oten entails creating a VM for the sole or partial purpose of hosting that app. The app dictates the OS, not vice versa any more. And observer1101 is right - that trend may have had a minor beginning in 1999, but it has grown very strong since. Azure or AWS is basically the business of running operating systems in VMs on demand for apps.

Yes, I fully understand and agree with all of that. However, I think it is still not accurate to say that apps run operating systems. More accurate to say that apps embed operating systems or are themselves bundled with operating systems (such that they can run on bare metal). And, MirageOS (http://www.openmirage.org/) takes this concept to its logical conclusion.

Haha, my bad. They run on Windows

Clearly you've never heard of MirageOS or erlangonxen. Look them up. The app is the operating system in those.

You're wrong on both counts. I mentioned MirageOS in the other thread, in fact. MirageOS merely links in the minimum portion of the operating system required to support a particular application. I still would not consider that to be 'the app running the operating system'; i.e., if you examine the application's call stack (with a kernel debugger and OS symbols) at any point in time, there's still going to be a lot of 'OS' stuff below the main entry point to the application.